


The Spark Knows Best

by Technoblade



Category: Transformers (Unicron Trilogy), Transformers - All Media Types, Transformers: Energon
Genre: M/M, Size Difference, Soulmates, Sticky Sexual Interfacing, Transformers Plug and Play Sexual Interfacing, Transformers: Energon - Freeform, battlefield romance
Language: English
Status: Completed
Published: 2019-08-29
Updated: 2019-08-29
Packaged: 2020-09-28 23:49:30
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 7,829
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20434529
Author URL: https://archiveofourown.org/users/Technoblade/pseuds/Technoblade
Summary: [TF: Energon] Prowl knew that he was drawn to Rodimus Prime out of a sense of duty, but it was not until the great civil war waged on that both he and the Autobot Commander began to realize that something else may have been at play. Was it simply infatuation, or could personal feelings really point to a deeper connection between two souls? The Spark was a mysterious thing, after all: when it wanted something, it would stop at nothing until it was victorious. Primus had made sure of that.





	The Spark Knows Best

**Author's Note:**

> I've been wanting to get this out for years, and now that I've actually done it, I can finally be at peace and slip into the sea with my self-indulgent nonsense.

There were three major tenants burned into the processors of every mech that successfully graduated from the Peace Enforcer Academy: first, Cybertron’s peace and governance takes precedence over an Officer’s personal safety. Following that, the lives of each and every citizen were to be taken into account when making a decision. And, to some, the most important of all was that, with their status, they became the working hands of the reigning Prime, meaning disrespect to one’s brothers in arms was to disrespect the leader of their world. Most Enforcers held these standards closely to their sparks, and did all in their power to ensure that those they had sworn to protect would see them as a force of good.

As he had risen through the ranks, Prowl was no exception to this mindset. The energetic young mech was smaller than nearly all of his colleagues, but he had made up for it in bounds through his determination, a caring nature, and a sharp mind that made his quick thinking seem just as blindingly fast as his tyres when they hit the ground. Those that judged him by size and personality alone found themselves proven wrong almost as soon as he set to work.

Being such a valuable asset as he was, it was no surprise when, during the battle for Central City, the officer was quickly recruited into the Autobot army’s fold and shot up through the ranks at a startling pace. With every conflict Prowl gained notoriety, and with it a sense of pride and joy. Truly, he was making a difference in this war--one that he had never wished to fight in the first place. The Decepticons, who, until that point, had simply been another group of citizens under his watchful eye, were now simply targets down the sights of his blaster. It pained him to his very core; how could this have happened? Why? 

For answers, he and so many others looked to those at the head of the conflict: the Primes. As the speakers and disciples of Primus, it seemed reasonable to most that they, above all, would know how to quickly end such a conflict. First, there was Optimus Prime: having only received his title and blessings just as the fighting began, with blaster fire beating down upon the door to Primus’ chambers during the abridged ceremony, he was very inexperienced, and it showed. Prowl knew him well, however, having trained the mech personally within the Peace Enforcers; he knew that Optimus was incredibly patient, almost to a fault, and was always looking for non-violent resolutions whenever possible. With that, however, came a sense that he might hesitate at the wrong moment.

Such was a point that Rodimus Prime had made quite clear he believed almost as soon as their Creator’s newest Son joined him in Command.

Where Optimus was reserved, Rodimus was bold and endearing, with a voice and personality so strong that even the most hardened of soldiers were captivated when he spoke. The people trusted him, and with that trust came a clear sense of just who was in charge at the beginning of everything.

To Prowl, it was the most intoxicating presence he had ever felt, and one that he would have given his spark for, if only to bask in it its glory for the rest of his days.

At first, he thought it a mere fluke when his spark and field seemed to practically burst when Rodimus Prime had addressed him directly upon their meeting. It was just after the citystate of Iacon had begun to crumble, leaving countless sparks at risk of destruction. Both Prowl and his partner, Checkpoint, had stayed behind to ensure the safety of as many Cybertronians as they could, no matter the faction they may have hailed from. When the fires began to die down, and body counts were taken, the Primes emerged from the ashes to observe, and to speak with as many as they could. A cold shudder had snapped down Prowl’s spinal struts as he and Rodimus locked optics, and the then-leader of the Autobots silently made his way across a rubble-strewn street to address him directly.

“Officer,” he had said, in a tone so smooth and soothing that it could heal even the most hardened of sparks, “you have served your people well, and you have my thanks.” He held out his servo, burned and dented from some extreme conflict. The gesture had barely registered in Prowl’s processors; his gaze was locked firmly on the stunning blue optics that burned in front of him, that came closer as the weary leader kneeled down. “Officer…?”

“S-sir!” Awkwardly, Prowl attempted to snap to attention, only to notice then that his arm would not respond to his command to salute. He tried again, jerking his shoulder, but to no avail; he glanced over and felt his spark sink. At his side the limb was hanging loose by the cables from its socket, cracked and still leaking fuel onto the battered pavement beneath them. How had he not felt that before? “I… I apologize for disrespecting you, sir. It… seems I can’t salute right now.”

Rodimus shook his helm. “No. No, there is no need for that. It is I that should be saluting you.” And before Prowl could form a rebuttal, his optics widened in surprise as the Prime raised his wounded right servo to his helm crest, holding it there for far longer than necessary. In all of that, he never once looked away from the smaller mech’s optics. “Thank you for your service.”

It was then that he helped Prowl stand, and led him towards the medics that scrambled at the small encampment to help those that they could. Optimus seemed to be doing his part as well, soothing the wounded with words of encouragement and thanks while energon leaked from massive wounds in his chassis. A glance was cast in that direction until he noticed that Rodimus had stopped, and was personally helping him onto a makeshift medical berth. “Sir, I--”

“Rest now,” the Prime directed, “so that you will be ready for another day. When you feel well enough to salute, I suspect you will be leaping into the fray again, hmm?”

Through the entire process, Rodimus’ servo had never left his frame; the tyres on his shoulders, his servo, the damaged arm that swung at his side, some part of him was always in the gentle grasp of his Commander. But when it finally withdrew, and the Prime stood to make his leave, Prowl felt his field flare out a moment, as though his spark and frame wished to protest as one. It made the other mech pause, glancing at him curiously before something seemed to stir in his own mind. But they both held their glossa, and Prowl watched wearily as charred and battered frame moved into the crowd to continue his walks.

In that moment, though he knew not why, Prowl realized that something within him never wished to be away from Rodimus Prime for long.

Numerous deca-cycles would pass before he had another chance to say something, but the odd exchange of words that came would forever change his life, and that of the flame-throwing Prime in turn.

Yet another argument had broken out between the Primes; it was uncertain just what the igniting point had been, but one moment, the door to the war room had been closed, and the next, young Optimus was shoving his way out with his Second in Command, Jetfire, following closely behind. A seething anger rippled from the Commander’s EM field, and it was enough to keep most onlookers at bay. Despite being rational and calm in most instances, there were moments that he would lash out simply to put some distance between himself and the universe at large. Such a sight made Prowl’s spark ache: he knew this was not who either mech was. 

Both wished for nothing but the best for Cybertron: peace and equality for all who wished to call it home, and to stop the sudden and terrifying rampage of the rogue Megatron. When it came down to it, the two Primes shared a particular brilliance that all around them knew could solve any problem--when they got past their differences in command styles first, that is. They would argue tactics and strategy, troop placement, supply transportation, nearly every aspect of a campaign before one would storm away to clear their helm. Then, after a time, they would return with clear, renewed energies in order to finalize their mode of attack.

Such occurrences were unnecessary, more than likely, but when two mecha of similar resolve and strength were expected to share the Title and Duties of a position almost always held by just a single spark, there were bound to be issues that could only be solved by throwing a temper tantrum before seeing through the clouds of doubt in their processors. It made sense to Prowl, at least, who watched solemnly as his protege left the Command deck to speak privately with his partner. If only there was something he could do to help them, he thought; but what?

“I don’t know how you put up with him.”

The depth of those vocals was unmistakable: Rodimus. Snapping upright in his seat, Prowl looked to see the crimson Prime strolling slowly from the office, lighting a cy-gar as he moved to sit down beside the officer. Ultra Magnus had not left the room just yet, which sent a burst of ease out through Rodimus’ EM field. That was unusual; more often than not, the Prime’s lifeforce seemed more guarded. He eased down in the seat, with one leg strut outstretched in front of him, and the other bowed outward. It was far from professional, but a clear sign of exhaustion from someone that typically took great pride in their appearance.

“Uh… sir, I’m… not sure what you mean.” Prowl tried to force himself to relax as well. “Him who?”

A puff of blue smoke released from the cy-gar as Rodimus pulled it from his lips; Prowl had never seen how smooth his features were this closely and clearly before. “You trained Optimus, yes? How did you manage it? He’s so… rigid.”

That caught the officer off-guard. “Well… yes, sir, I was in charge of his one-on-one training in the Enforcers. We got along just fine, at least in my professional opinion. But, I never helped with any of the combat training, just… civics. Learning how to handle the people we served.”

“Hmph. Well… not to speak poorly of your teaching skills, but I don’t quite think he picked up on how to solve problems with his equals.”

It was the first time that he had ever heard the Prime refer to Optimus as anything other than another soldier, or, at worst, an interloper; but equals? His golden optics flicked back to the open office, where he noticed Ultra Magnus finally taking a seat, drained in his own right. Prowl looked back to Rodimus and offered a shrug. “There… wasn’t much of an opportunity for that. He seemed to get along with everyone, until the whole… um.”

“Until he accepted the Matrix. Right?”

While his helm had not turned completely, it was clear that Rodimus’ gaze was focused on him, though it was not in a way that felt hostile. Rather, it was curious--that same curious look that he had given back on the battlefield so many lifetimes ago. “To those that have carried it, the Matrix has been known to… well. As a collective knowledge of all Primes before us, you could say that it has a lot to… say. It can be a bit overwhelming at first, which would turn even the calmest-natured spark into someone with quite the temper.” Another puff, and he blew the smoke up into the air. “Magnus told me that I have leveled out with time, but his brother needs a bit of work. And me, he said that I just need to calm down for once in my life. Can you believe that?”

Such a candid conversation was unnerving, but only on the surface. As he spoke, Rodimus’ EM field seemed to unfurl, a clear attempt to diffuse the stress that had been building in his frame. It gave off waves of discomfort, an almost static-like feeling as it crawled across the joint seat to temporarily reach at his own before pulling back inward. More than likely, the Prime did not allow for such release around just anyone--for him to relax in front of someone like Prowl, it showed a great deal of faith. That did not go unnoticed by the Officer.

“Well, sir, you seem to be doing pretty okay to me,” he said sheepishly, which got a snort of amusement from his Commander. “But… I guess that means he might have it with him right now, right? The Matrix. From what we went through, he was never that angry or upset.”

“Yes, he does. I’ve held it for… damn… close to thirty million years, at this point,” Rodimus replied, glancing up at the ceiling. “If we are both to take this mantle, he needs to get used to it. And me, I need to remember what it’s like to have some silence in my spark.” The smile he had held briefly fainted some, forming into what Prowl could only describe as a show of true confusion. “...Prowl, was it?”

“Y-yes, sir?”

“Are you an Outlier?”

Where was this going? “N-not that I know of, sir. I’ve never shown signs of it, anyway. Unless, uh…” Was this the right time to crack a joke? If not then, then when? “U-unless you count being deceptively cute to be an Outlier ability. N-not that I’m trying to, uh… brag about it, o-or anything.”

And that was what brought the smile back to the Prime’s face. The plating on his chassis flared slightly as he took in another drag off the cy-gar, releasing the plume of sapphire smoke along with the pressure in his frame in one go. “It isn’t often I get to relax, let alone speak with someone that isn’t a direct advisor.” He shifted slightly to take in the smaller form with one sweeping glance of piercing blue optics. “I could use more times like these, I think.”

Prowl’s spark nearly burst from its casing as he held Rodimus’ gaze, and, instinctively, a servo quickly swatted at his chest plates as if to silence the thing; that earned him a quizzical smirk. Before he could stop himself, his vocoder seemed to speak more from his feelings than his more logical side would have liked: “I-I might be able to help you relax, sir.”

Silence. A hard, calculating stare coupled with the same smirk as before, bearing down on the smaller mech as his faceplates began to flush red with embarrassment. Please, he thought, don’t take it like that. ...Although, deep in his spark, he felt no protests from his conscience. It might have even been something he wanted--despite being so completely inappropriate on levels that even the courts wouldn’t comprehend--and of course he had fantasized once or perhaps fifteen times, but who hadn’t? This was Rodimus Prime.

“Do you… know what you’re volunteering for, soldier?” The word was said with such emphasis that it could be felt in every micron of Prowl’s frame. “And are you…  _ actually _ volunteering? Or just being… what was your verbage… _deceptively cute_?”

Prowl reset his vocoder three times before the sputtering of static stopped. He offlined his optics for a moment, shook his helm, and let out a heavy burst of air through his ventilation systems before looking back up. Rodimus had not moved. “S-sir. It would be… a huge violation of… every possible code in the book.” No change in his commander’s expression. A yes or a no: that was what he was waiting for. Again, the Officer reset his vocoder, and felt the flush in his faceplates burn hot enough that it almost hurt. “Sir. ...Yes, sir. I was. A-and I accept any and all repercussions for speaking… so out of line. I-it was an abuse of the situation, sir. I’m sorry: it won’t happen again.”

The smile that had warmed him inside and out flickered a moment on Rodimus’ face, which, in the moment, was more frightening than facing down an entire battalion of enraged Decepticon fighters. Was he angry? Upset? 

“Don’t apologize; you’re not in any trouble,” the Prime replied calmly. After twirling the cy-gar between his digits, his thumb grazed the side of it and snapped the burning core inside of it out. The power of flame was quite the interesting Outlier ability. “I was the one that came to you, after all. Which… well.” He paused, as though he was struggling to pull two thoughts together in his mind; after a few long nanokliks, realization flashed across his features. Prowl watched carefully as the Prime glanced down at his chassis, frowned, then looked back at the Officer; he was thinking. “I need to know something. Yes or no? And--don’t interrupt me, soldier--do not think of this in terms of Chain of Command. What is  _ your _ spark telling you?”

Prowl’s spark pulsed harder. His? Why such emphasis? “Yes, sir--yes. I-if I’m just talking from my spark, a-and not because you’re… you? ...I want to get put straight through your berth.”

The bright blue of Rodimus’ optics flashed a moment, clearly startled, before settling back to their natural hue. “...Not quite what I was expecting, but. Alright. My quarters, thirty breems--I will ensure you are dismissed from your duties tonight.”

“B-but what about--”

“Optimus needs a night to sit out with his thoughts. We know Megatron’s forces are at a stand-still right now. Do not worry about that.” He stood to his full height then, stowing the cy-gar away in his subspace before stepping back into the office. The door closed, and with it, the connection that Prowl had felt so strongly between their souls, practically jumping from their chestplates to scramble for one another, snapped away.

==

The residences of High Command were small, by most opinions, but still larger than the bunk rooms that the regular troops were crowded into. Prowl stood just a few paces inside as the door swept closed behind him, leaving the Officer feeling oddly exposed. A small, private washrack was tucked off in the corner of the room, a table and some chairs in the center, and against the back wall, a berth that looked large enough for a mech at least twice the Commander’s size. 

Rodimus, in turn, seemed to have calmed from his spell of uncertainty before. With a cube of fuel in each servo, he motioned for Prowl to follow him to the sitting area in front of the berth. Dutifully, the Officer obeyed, choosing to sit across from the mech now offering him some rather weak high-grade. 

“I-it’s pretty comfortable in here, from the looks of it,” Prowl sheepishly commented, hoping to break the silence. Much to his disappointment, Rodimus didn’t react to the comment; while no longer uncertain, there seemed to be something else on his mind. “Sir, if you’d rather I go, o-or we just--”

“No. My apologies.” His Commander shook his helm before taking one of the open seats, shifting to lean his elbows on his knees as he looked at Prowl. “Believe it or not, you’re the first to pass through that door--the only one. I receive more proposals than you’d think, but none that… hmm. Tell me. What is it you felt when I sat beside you earlier? You looked startled, and your field told more than your words did.”

Prowl shifted some in his seat. “It… i-it was something that… uh. This… I’m sorry if this sounds weird, sir, but… it felt like your spark was trying to talk to mine. A-and I’ve never felt that before. So I didn’t know how to react.”

As the words came, so too did the flash from Rodimus’ optics. “And you’ve really never felt that around myself, nor anyone else before?” His gaze seemed to ask a deeper question: Was it real?

“With anyone else? No. Like I said. But, um… that… when we first met--in Iacon? I felt it a bit. But this was… really, really strong,” Prowl explained, pausing to sip his fuel. It was far weaker than he wanted it to be. “I didn’t think much about it that day, cuz I was so tired, but I’ve… thought about it since then. A lot. And--if this freaks you out a bit, I understand. Because it kinda freaks me out too. ...But, if I can be candid?”

A nod. “Go on.” He was waiting.

“Okay. ...Sir, since then, I’ve felt like I… have to be here. Right here. N-not in your room, but like… with you. Heh, wow… now that I’m saying it out loud, it’s so weird.”

But the expression he received was not what he had expected--disgust, annoyance, or amusement of some kind. To him, it looked like.. Acceptance. Relief?

“It isn’t weird at all. In fact… it takes quite a load off my processors,” Rodimus admitted. His optics softened, their blazing blue fading slightly to a more comforting, almost soothing hue. A servo moved to brush across his chassis, just over where Prowl assumed his spark chamber was. “But I’m going to ask you just one more time: Yes or no? Do you wish to proceed with this proposal of yours, or stay here and talk?”

Relief. The feeling shot through Prowl’s field in a massive burst, bringing a surprised look from the Prime. Not only was he not in trouble, but Rodimus seemed to understand--no, he reciprocated the feeling, at least to some extent. As he focused on the moment, drowning out the dull background noises of the room and base around them, he felt his spark begin to swell: something was echoing the very same tones that his life force was calling out into the ethos, with just as much confusion and intrigue as his own. “Yes. I do.” This time there was no hesitation to his words, no awkwardness or doubt.

This is what they both wanted.

“Very well. First… I have to know: what is absolutely off the table for you? What am I not allowed to do?” Rodimus’ expression remained open and understanding. It was not a question meant to mock, or even to see what he  _ could  _ do. He wanted boundaries. With his questioning alone, nearly every rumor regarding his berth life had been dispelled.

Yet when it came to his limitations, Prowl paused a moment to think. Had he ever needed boundaries? Things with Checkpoint never got very exciting. “Uh… to be honest, I don’t know. I guess I’m not opposed to anything, but I’ve never done a lot outside of just… cables plugged in and regular interface.” Was that bad? To him, it almost sounded weak to admit it, especially to his commander.

However, his answer was met not with laughter or amusement, but with a calm, understanding nod. “I want us to be comfortable, here. If my thoughts on this are right… our frames might react a bit more… enthusiastically than either of us is used to. The last thing I want is for you to be hurt. So…”

“W-wait. What are you thinking?” Finally, an opening to ask it. Prowl set his fuel down and leaned forward, while his field flicked outward with curious pulses of energy.

Without a word, Rodimus stood and crossed the short distance between them before kneeling down in front of the Officer’s seat. Prowl sat up a bit straighter, puzzled, while his small servos were taken into the other’s grasp. In a soft, soothing tone, the Prime said, “There have been many times that I have walked among the people without the Matrix’s constant droning in the background. But tonight… this was the first time in my many vorn of life that I’ve felt a tug in a different direction, to something away from my duties. I don’t know what to call it, but I believe that I… want to feel it more.”

For many centuries the question had been asked, to what extent was a Prime to give themselves away and receive nothing in return? Was such fraternizing even allowed? They were, at their core, still very much Cybertronian: everyone had their own needs, some of those more deep and intimate than others. Was giving into the calls of their baser programming wrong? As he had never imagined himself being in such a situation, Prowl had never particularly cared one way or the other. Yet here, and now, as he felt a pull so strongly towards the mech with the soulful optics that it nearly made him want to leap from his chair? He only wished to tempt that fate.

It took a great deal of courage to close the gap between them first, but Prowl allowed his hesitation to melt away in that very moment in order to lean forward and place a gentle kiss on Rodimus’ cheek, feeling his faceplates begin to flush again as he pulled back. “Sounds like a good plan to me. I don’t know what it is either, but I think I really, really like it. A-and maybe if we figure it out…?”

A chuckle. “Then, perhaps, yes. Maybe afterward I can get back to work and end this blasted war so that we can focus on whatever  _ it _ is.” 

==

Two massive digits pumped in a deep, heavy rhythm within his valve, twisting, scissoring, scraping their way across every node within their reach to find just which ones pulled the most satisfying cries from his vocoder. Thin, flat-ribbon cables stretched between the pair on the berth, connecting processors and ports to send flares of electricity and power back and forth between their joined frames. Prowl groaned and panted needily as Rodimus prepared him, held in place by a single servo pressing down on his abdominal plating. It was exciting to be restrained, even if he could still move most of his limbs: the additional pressure was mixed with the dull heat of the Prime’s inner flame, coaxing the smaller mech’s core temperature higher with every ministration.

“P-p… pl… ea… se..?” Prowl’s vocals were laced with static, but were met with a dull tone in response:

“Please, _what_?”

Within him, the probing digits had paused, and the bright blue optics of his partner stared at him impatiently from above. It was an act--they had agreed to it beforehand, thinking it would be just an additional layer of intrigue to their ridiculous plan, but it still felt so real, as though this were some exercise in combat.

“P-pl… please, s-sir.” It took everything in him to pull the words from his throat, but as soon as they came, he received his reward: Rodimus’ servo withdrew for only a fraction of a second, within which he brought a third digit into the fray. Slowly, tenderly, he began to press all three inside at once, which brought a gasp out of the smaller mech. He attempted to arch upward, but was pushed down again and held tightly to the berth.

“Move again and I’m getting the restraints.” A warning, but not one that was to be taken as a threat: it was an idea for later. 

The shifting stopped, but was followed by a short, needy whine as the pace began to pick up again. Halfway in, then out, then completely inside in one push; twist, open, close, retreat. It was forceful, dominating, controlling--everything that Prowl never realized he had craved from a partner. He clenched around the intruders, as if by sheer will alone he could get them to go in deeper, to press against the top nodes of his valve and make him beg for release. That permission had not yet been granted, however. He needed to earn it.

“You’re going to overload,” Rodimus growled, increasing his speed. “And once you do, once you prove you are _worthy_ of receiving me, we can move forward. Understood?” Again, he paused.

Prowl’s hips quaked. “S-sir, y-yes, sir!” Then, his optics flashed brighter and brighter still as the movements became harder, and he could have sworn, somehow, went deeper, until, on the fourth shove, his systems were finally given release. He clenched down hard around Rodimus, and arched up all that his Commander would allow in order to pull the servo as deep as possible. Fluids leaked out and onto the berth, coating his thighs and the Prime’s lap in turn, until finally his systems began slowing down. His extremities twitched slightly, and his hips quaked with the after-tremors of his first overload of the night. At some point, his optics had flashed offline, rebooting only as he was being moved just a moment later. 

It was time for phase two.

Rodimus moved to settle between his legs, taking one strut in each servo before lifting them upward, shifting his smaller form to better view his valve. It was swollen and heated, the light blue protomesh glistening with his fresh fluids, while yellow biolights glinted around his anterior node and half-pressurized spike. In any other instance, embarrassment would have flooded him--but with the cables that connected their helms and chassis, Prowl felt a sense of ease and enchantment flow through and into him. Rodimus was enthralled, despite the gruff, controlling tone that he took; it was all part of the act.

“Just as instructed. Very good, soldier.” While shifting Prowl’s legs up over his shoulders, Rodimus leaned his helm forward to taste the prize he sought. It brought a sharp gasp from the smaller form, who squirmed in response to the probing glossa’s heat and pressure against the malleable surface. The Prime hummed with amusement, sending energy in slow, crushing waves through the cables as he kissed the outer folds slowly, tenderly, then delved inward, possessive of this writhing frame within his grasp.

All that the Officer could give in return were gasps and short whines of pleasure, while his servos scrambled beneath him for purchase. The mesh blankets caught in his digits first, and he held on tight despite knowing that they wouldn’t keep him in place. His thighs were held tightly as another vibration was sent up through his valve, where Rodimus had tilted his helm just enough that his nasal ridge would grind against the anterior node while his glossa dragged along the tight cluster of nodes at the valve’s entrance. Prowl let loose a frustrated groan; he wanted nothing more than to rock his hips forward, to push himself over the edge that his frame was being dragged toward so carefully, so lovingly.

It made his spark sing with delight, a joyous sound that was echoed almost perfectly by the Prime’s soul so close at hand. It seemed that neither of them had experienced such a sensation before, as mutual surprise caused the data cables nearest their spark chambers to become backed up with energy for a moment, before a slow, heavy release allowed both frames to relax just a bit more. 

That was when Rodimus began to pull away. 

Prowl’s optics reset twice, and he looked up--down?--to see the Prime’s face move away from his interface array, coated in a glistening layer of fluids. With passion in those blue optics he seemed to keep his gaze on the smaller form, easing his partner’s legs down off his shoulders and around his waist. The change in position allowed Prowl the great relief of leaning on his elbows, and he adjusted just in time to see Rodimus pause.

Now resting against Prowl’s pleading array was a fully-pressurized spike. It seemed a bit shorter than his daydreams had imagined, but in the low light of the room it was clear to him that it would still fit snugly inside him, with its simplistic but functional modifications. And yet, the Prime continued to hesitate. A buzzing of uncertainty filled the static of the data cables, which made the smaller frame tense; he had to think of something, and with an overload so close, he was getting desperate.

“S-sir! P-permission to… to sit on your lap, sir!”

“What?” There was a flash of blue optics as his Commander looked up, snapped from his daze. He was worried. “To… oh. Yes… yes, by all means, soldier: I think you’ve earned it. Do a bit of the work for once, would you?”

The sudden change in course allowed relief to spill back through the lines. While the heavy grip on him was relieved, Prowl managed to awkwardly push himself up so that his legs were on either side of the Prime’s, and he braced himself against the massive shoulders that had been tantalizing him all evening. The other’s servos sat lightly on his hips, a patient, loving guide, as he fell into the open sea that was Rodimus’ stern, passionate gaze. The show would go on. “Get to it.”

“Sir, y-yes sir…” Without warning, he leaned forward to capture Rodimus’ lips in a kiss. He could taste himself there, and he lingered as curious digits sank into his hip plating, toying with wires there as the blunt tip of the spike brushed past his outer folds and pressed firmly against him. The Prime rumbled his approval, sending a wave of thanks through the data lines, just as Prowl began to sink down to meet his hips.

Except, it was less sinking, and more the blue mech rocking himself back and forth as he felt his calipers stretch to their limits. He whimpered with delight, shuddering as he worked to deepen the kiss, and he didn’t stop until his aft sat flush Rodimus’ thighs. It pressed firmly against his ceiling node, which made both mecha shudder; the Prime’s servos clamped down on his aft plating while his valve clenched tightly, refusing to let go. Prowl rocked his hips with a deep sense of urgency and determination, not wanting the pressure to change: it was a perfect fit, stretching and pressing in all the right places.

It was Rodimus that broke the kiss first, and dropping character as well. He wrapped his arms around the smaller form and buried his face in Prowl’s neck cabling. There, he muttered, “Move when you’re ready. I won’t hurt you.”

Such kind, genuine encouragement was what they both needed then; with his arms now around the larger mech’s shoulders, Prowl eased himself up just enough to feel the deep ridges of Rodimus’ spike drag along the dense node clusters within him. He rocked back down then, feeling himself filled and pressed firmly to the other’s array, before repeating the motion once, twice, and then a third time, where he slammed down hard enough to make Rodimus jolt, and pushed himself into another overload. His valve clamped down and pulsed greedily, which his partner took as a sign to buck upward until sweet relief swept over him as well. Heated transfluids filled and overflowed within him, and the pair held tightly to one another as the waves of pleasure surged through their joined systems.

When the sensation finally began to ebb away, the pair sat in silence, embracing one another as though pulling away would be the end of their lives. Prowl’s spark roiled within its casing, pleading desperately to be allowed to bask in the glow of the one it knew was so close by--the one that it claimed was its match. The officer hadn’t ever considered the notion of having a soul mate, let alone finding them, but for it to be a Prime that his being cried out for? That seemed more than impossible--laughable, even.

Yet here he was, bucking gently beneath his frame, optics dimmed as he simply listened to the gentle purr of Prowl’s engines. The sight made the smaller mech smile, and he turned just slightly to kiss the side of Rodimus’ helm. “D-do you… want to keep going?”

“In a moment. I was… afraid of hurting you.” The Prime’s words were so soft then, a cushion of tenderness that seemed almost uncharacteristic of him. “Did I?”

“N-no! Nnngh… Pits, not even close. S-sorry, I’m j-just a bit… m-my spark…”

“So… it isn’t just me, then.” 

“W-what?”

There was a gentle shifting of metal, just against his chassis. Prowl blinked, then leaned back just slightly to watch as Rodimus’ chest plates opened between them. It wasn’t enough to fully expose his spark--only a bit of light poured out, a burning red light that matched the fires he lit on the battlefield. There was a gasp that caught in his throat, and before he could stop himself, his own chest plates parted to match, with a dull green glow eclipsed by the soul just beyond its reach.

“I’m… s-sir, I’m…”

“Do you want to stop? A… a merge wouldn’t be wise,” the Prime said carefully. “Not when… not when this is happening. Primus…”

“N-no, no I w-wanna keep going. I-if you do, anyway.” It was a night that he never wanted to end. His gaze lingered in Rodimus’ optics, which seemed to be searching him for any sort of hesitation or discomfort, but none could be found. “T-this is… so much more than I was… expecting…”

“Mmm. I can… second that.” A servo continued to trace along the lines of the smaller mech’s aft, moving up to brace him as Rodimus leaned him down and onto his back. Gentle kisses were placed along Prowl’s neck, who purred and whimpered in reply, locking his legs around the Prime’s waist, wriggling his hips in excitement. A smile crawled across the larger mech’s features, and he said, “But if you insist… I think I can continue to break the rules, just this once.”

He pulled back so that his spike was only partially seated within Prowl before rolling back forward with a hard, pointed thrust. It brought a sharp cry from the other’s vocoder, but a shock of pleasure and lust coursed through the cables and back into Rodimus’ frame. Clearly, that was the right way to go with this. It was a heavy pace that he kept only by pulling their frames flush together. It allowed their sparks to mingle as well, though they were still at a safe enough distance that they could not touch. Tendrils of light spilled outward, swirling together just on the brink of becoming one, but were ultimately denied such a pleasure.

Prowl, determined as ever, attempted to rock back into the motions, but ultimately melted into a dazed heap within the Prime’s arms, pinned down to the soft, cradling berth as every node within his valve was lit ablaze by ribbing and ridges that seemed to be mapped perfectly to match him. It was as though they had become a unit in that moment, two minds blurring into one unified soul that was bound by trust and faith. In time, they would find that such a combination would come on a much deeper level as well.

Until then, the plane of existence that they had found themselves on in that moment would do just fine.

==

Only a century would pass before their next physical encounter, though this one was much more public than the last. In the heat of battle Rodimus had been thrown clear through a makeshift shelter by a Decepticon Combiner. Three mecha had somehow merged to become one, transforming together in order to over-power the Prime within mere seconds of their change. His frame bounced across the ground as though it were a mere toy, skidding to a halt beside a small group of scouts that had been cornered inside.

Standing at the front of the pack, using himself as a shield against whatever was to come, was none other than Prowl.

Before the dust had even cleared, the Officer scrambled to his side, acting as a crutch for the dazed and battered Prime. “C’mon… you’re gonna be okay, sir, but you’ve gotta get up!” Almost instinctively, his spark reached out through his field in an attempt to empower the other’s, but was met with an odd sensation that startled him enough to make the smaller mech yelp with surprise: the Matrix. It snapped at him through Rodimus’ field, who only then was coming to his senses. The Relic was rather protective of its charge. “Rodimus…? Sir?”

“Combiner,” the Prime grunted, and he waved at the pack of Autobots behind him, the urgency in his tone taking a turn towards panic with every nanoklik that passed. “Take cover--he knows I won’t die from--_DOWN_!”

A fist came crashing through what remained of the wall, followed by the fused mech that had wildly thrown the punch. Rodimus, in turn, grabbed onto Prowl and turned away from the opening, guarding the smaller frame from falling debris. “Go, NOW!” The words were far more harsh than he had wanted, but the scouts knew to move when a Prime told them to. However, the Holy Relic within his chassis seemed to react negatively to something, sending a sharp, biting pulse through his frame and field. Both he and the officer in his arms winced, but the feeling was gone almost as soon as it had come.

Rodimus turned and fired on the Combiner, who fell backward into the hole from whence he came. “Go, Prowl. _Now_.” Again, the Matrix reacted--it never reacted to the things he said--at least, it hadn’t for millions of years by then. He glanced down at his chassis in confusion, then at the mech in his arms, who stared at him defiantly. They were running out of time. 

“It wants me to help you. So… let me _help_.” Determination filled Prowl’s optics, and his field flared out to match it. A servo moved upward to rest against the invisible seam in the Prime’s chestplates, where he felt the familiar pulsing of the other’s spark, intertwined with the mighty ebbs and flows of the Matrix’s divine energies. “Yes. I do want this.”

That was all it took to gain a weary smile from the only mech his spark had ever sung out for.

Just outside the building, a number of Autobots were converging on the scene. Optimus Prime led the charge, vaulting into his root form from top-speed as he drove toward the crumbling structure. “Rodimus?! Where are--”

He was cut short by the sounds of metal tearing and crunching nearby, and was given only seconds to dive out of the way of a massive frame flying up from the building in front of them. Except, this wasn’t a flier: it was an odd amalgamation of three distinct colorsets, none of which had wings. Somehow, it had been launched upward, and came crashing down in a massive heap just beyond the confused group of Autobots.

“You’d best retreat now, Gravion. You’ve suffered enough embarrassment for one day.”

From the hole in the side of the building stepped another massive form, though this one was a bit more familiar. At least, in parts it was. Optimus’ expression changed to one of shock and confusion behind his mask. “Rodimus…? What in the Pits…?” The upper half of his frame was distinctly his own, though altered some so that most of his bulk shifted to cover his back and sides. His legs, however, were another story entirely: the plating was much lighter, allowing him to move faster as he climbed out and towards the fallen Decepticon. What stood out most was the unmistakable red and blue lights that now shielded his spark chamber, and the cavity occupied by the Matrix. 

Prowl…?

The Decepticon Combiner pushed up from the ground with an angry snarl, and shot the pair of Primes an angry glare before splitting back into three individuals that took off in different directions. Rodimus held up a servo to the group of onlookers and shook his helm. “No. Let them go. The two of us were more than enough to teach them a lesson.”

Before anyone else could interject, he too split off from the mech attached to him, catching Prowl in his arms as they both settled back in their root forms. A grand smile broadcast Rodimus’ pride to the team around him, which swelled outward into his EM field, and bled into the mirthful waves that coursed from the smaller mech’s frame. In that moment, the two were synchronised on a level much deeper than what could be seen.

Two souls had merged into one, and their combination would never come undone.

Murmurs of surprise and approval spread through the troop, but Rodimus’ gaze ultimately settled upon his fellow Prime’s concerned optics. “Thanks for the backup, Optimus, but I believe it’s time for us to return to base; you missed all the fun.”

Heated air pushed roughly from the other’s ventilation systems, a show of frustration, but no comment was made; Optimus nodded in agreement and turned to the group. “Fall back, team. Good work.” He turned back just as Prowl was set gently on the ground, and he could see the connection that the two now shared; it had not been forced, not taken greedily by one from the other in an imbalance of power. No, this had been a blessing handed down by those that watched from beyond: the souls of those that guided the Primes knew when to cast their judgement, and in that moment, the decision was abundantly clear.

“Don’t be jealous: perhaps your time will come as well.” Rodimus was smiling still, but he had moved to clap the other Prime on the back with an open servo; it was still hot from an earlier use of his powers. “Until then, I believe I must abscond with your teacher; is that alright with you?”

Optimus merely rolled his optics and vented another sigh, while Prowl seemed to blush furiously from the sidelines. There were no arguments to be made here--not when Primus and their predecessors had already spoken. “Just… make sure you’re actually awake in time for meetings from now on, would you?”

Rodimus flashed a self-satisfied grin. “Yeah, that’s not going to happen any time soon.”

Though there was no telling where this path would lead them, Rodimus felt content with the fact that, for once in his life, there was someone by his side that wanted him for more than just power and notoriety; their connection went far deeper than that, and only a fool would have considered Prowl to be so jaded. From then on, they would be an inseparable unit, one that truly reflected the rallying cry of the Autobots: Until All Are One.


End file.
